Fusion projectile



w. NICHOLAS 2,417,437

FUSION PROJECTILE Filed Aug. 6, 1942 Jrwem fm wiuium Nicholas Farch 18,1947..

Patented Mar. 18, 1947 FUSION PRGJECTILE William Nicholas, United StatesArmy, Chicago, Ill.

Application August 6, 1942, Serial No. 453,774

(Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 O. G. 757) 9 Claims.

The invention described herein may be manufactored and used by or forthe Government for governmental purposes, without the payment to me ofany royalty thereon.

This invention relates to missile for offensive action and is applicableto all such missiles, whether thrown by hand, from a gun or any otherprojecting means. In particular it has reference to a missile which isdesigned to adhere by Welding action to the structure forming thetarget, so that its work of destruction will be more thoroughlyaccomplished. For example in the case of a tank vehicle. the missile, ifintended for incendiary action, will fuse and adhere to the tank bodypreparatory to the incendiary action which will proceed more effectivelythan if the missile had fallen away after impact or penetration.

The elfects are accomplished by providing a missile carrying a highlyexothermic component which is initiated in flight and a welding fluxwhich is prepared for functioning by the heat efiects of the thermiccomponent.

It is therefore an object of the invention to provide a missile designedto adhere to a target by fushion.

More particularly it is an object of the invention to provide a missilecarrying a weld-promoting fiux and a thermic component for cooperativeaction.

The specific nature of the invention as well as other objects andadvantages thereof will clearly appear from a description of a preferredembodiment as shown in the accompanying drawings in which:

7 Fig, 1 is an axial sectional View of a projectile embodying theinvention,

Fig. 2 is a sectional View taken on the line 22 of Fig. 1,

Fig. 3 is an axial sectional view of a hand grenade embodying amodification of the invention,

4 is a fragmentary view in section of another grenade showing a modifiedstructure,

Fig. 5 is a detail view of a firing mechanism, and

Fig. 6 is a top plan View of Fig. 5.

Referring to the drawing by characters of reference there is shown aprojectile body I having a reduced ogive 2 forming with the body I ashoulder 3 exteriorly of the shell, and a corresponding shoulder 5interiorly thereof, whereby the thicknes of the shell walls ismaintained nearly constant throughout. Spaced longitudinal grooves 5 areprovided in the ogive.

An impact firing pin 6 is provided in the central recess of a base plug1 and the pin is separated from a primer 3 by means of a spring 9. Afiring pin in is provided in the nose cap H and held forward of a primerl2 by means of a spring l3. Flash holes'lz' are provided for the primerl2 in the nose cap ll.

Within the body of the shell is a highly exothermic material l 4, suchas thermite. A similar material l5 fills the grooves 5 and is heldtherein by a covering shield N5 of thin metal conforming to the shape ofthe reduced ogive 2. An outer metal shield ll of a material suitable forpressure welding is provided in the form of the normal outline of thetrue ogive, and in the space between covers 16 and I1 is included a fluxmaterial 38 which may be a combination or mixture of an absorbentmaterial such as: activated charcoal, carbon or silica gel, with suchactive chemical agents as: sulphuric acid, ammonium chloride, phosphoricacid, and commercial welding fluxes.

Upon firing of the shell, the inertia firing pin Hi sets back andignites the primer L! which may be of any composition capable ofcommunicating ignition to the thermite l5. Ignition is carried to thethermite l5 through flash holes l2 or any other convenient means. Theheat developed by reaction of the thermite will release the fluxconstituent in the flux is by conduction through partition H5. Theliquid flux constituent will distribute itself thoroughly between theshield I! and the projectile body I by capillary action between the two.Upon striking a metal plate, the force of impact will actuate the basefiring pin 5 to ignite thermite charge M and the force of impact at'thefront of the projectile will cause a welding action between theprojectile and the metal target, the flux !8 providing the fiux means,and the shield ll serving as the welding rod.

At the instant of impact the thermite in the space between the ogive andshield 55 will be completely molten, but the thermite ill will be inert.

The relatively small amount of thermite used at l5 in the space betweenthe ogive 2 and shield it will function and upon engagement with thetarget the large mass of the cool target will absorb much of the heatcommunicated so that a. function occurs analogous to soldering orbrazing, whereby the projectile body is fixed in place for a time atleast. As the target conducts heat from the nose portion the latter willbe less quickly melted by the subsequent thermal reaction of thethermite i4 than the distant parts of the body I, and the latter will beruptured by the larger body of thermite and the molten product will bespilled on the target.

In Fig. 3 is shown a grenade embodying the invention. A conventionalfiring unit comprising a primer housing I9, firing pin 20 and handgripping lever 29' is shown on the grenade. The grenade body comprisesan inner wall 2i of porcelain or sheet metal containing a thermitecharge 22, and a network of partition 23 of screening or sheet metal,preferably soft and pliable are provided to quickly distribute heatthroughout the mass after initiation. Aluminum will preferably be usedfor the network since it is a good conductor of heat and in additionwill contribute in the reaction of the thermite.

An outer wall 26 of screening or perforated metal sheet is spaced fromthe inner wall 2|, and the space between the two walls is filled withflux material l8 of the type described in connection with Fig. 1.

Upon releasing the grenade from the hand, the thermite, ignited, willheat the flux, releasing the acid or flux constituent from the absorbentmaterial. The outer casing will be saturated with the flux materialimmediately after the thermite is ignited. After striking a metaltarget, the flux material will attack and clean the surface of the same,causing the outer casing 26 to weld to the plate. As the thermitecontinues to react, the molten metal product will flow, stick and freezeto the metal thus holding the grenade thereto. If the metal is painted,the heated flux material released from the grenade will attack thepaint, exposing a fresh metallic surface.

It may be understood that the welding of the wall element 24 to thetarget may occur without actual contact of the molten product ofthermite reaction, initially; or may be due to, or aided by, contact ofthe molten thermite mass. In the first case, the material 24 will be ata much lower temperature than the thermite product, but still readilyunited with a target with the aid of the flux material. In the secondcase, the thermite product in molten state will tend to fall away fromthe part of the target actually engaged by the grenade wall, and so onlya small amount will be present there, which may become quickly set byreason of the rapid conduction of heat therefrom, to and through thetarget.

In case the grenade strikes the side of a tank turret and fails tobecome attached thereto, but falls, it will land on horizontal orsloping deck or other cover parts, where gravity will exert less forcetending to move the projectile from its location on the target, and sopermit its more ready retention by welding and/or deformation of theprojectile, while the molten content escapes. This molten material islargely effective in gaining access to joints and interstices by whichoperating parts are prevented from functioning; by fastening closures;by effecting breaches in fuel tanks, as well as producing fumes bycontact with material in the target; by burning personnel; by causingdetonation of ammunition, etc. In its small size especially, it need noteifect a breach in heavy armor to be effective, and vertical armor platewill rarely be breached by being melted by the thermite of the device.

It will be appreciated that the wall 2! is comparatively fragile, andthat the wall 24 as described is moderately flexible, so that theprojectile tends to become flattened on impact with a target, which-inaddition to facilitating attach- 4 ment-will tend to prevent theprojectile from rolling on flat surfaces.

A variation of the flux compartment is shown in Fig. 4, wherein theouter wall 24 is fitted on an inner wall 25 and the latter is providedwith indentations 26 containing the flux 27. The indentations may besquare, circular or otherwise, and should be evenly distributed over theinner wall 25. Upon exudation of the flux liquid by heat, it willdistribute itself thoroughly between the outer casing and the innercasing by reason of capillary action.

In order to protect the outer surface of the inner casing and the Wholeof the outer casing from attack by the flux it may be necessary to treatthem, as by lead plating or by a plastic, acid-resistant coating.

In Fig. 5 is shown an igniting device which may be employed in theconventional igniter housing IS. A bushing 28 is drilled to provide abore 29 and the latter is tapped as at 33 for a portion of its length.Liquid phosphorus pentoxide 31 is placed in the tapped portion andassociated therewith is a charge of barium dioxide 32. Ihe latter may,however, be placed separately in the igniter housing 9 or within thebody of the grenade. A red 33 is slidingly fitted in the bore 2%}, andthe bushing has longitudinal channels 34 to admit air for oxidation. Thebushing will be so placed in housing I9, that the rod 33 will receivethe impact of the firing pin 29 and, sliding through the bore 29 willcause the phosphorus pentoxide to ignite by friction with the threads inthe tapped portion of the bore. This will in turn heat the bariumdioxide which will ignite the thermite.

I claim:

1. A projectile comprising a charge of highly exothermic weldingsubstance near the exterior thereof and a charge of welding fluxmaterial exteriorly of and adjacent said substance, and means toinitiate thermal reaction of said substance upon firing of saidprojectile.

2. A projectile comprising a, charge of highly exothermic substance nearthe exterior thereof, a charge of welding flux material exteriorly ofsaid substance, means separating said substance and said material, meansenclosing said material, and means to initiate thermal reaction of saidsubstance upon firing of said projectile.

3. Aprojectile comprising a body portion including an ogival portion ofreduced profile, a charge of highly exothermic welding substance at saidogival portion, a charge of welding flux material exteriorly of andadjacent said substance, and means to initiate thermal reaction of saidsubstance upon firing of said projectile.

4. A projectile comprising a body portion and an ogival portion ofreduced profile, a charge of highly exothermic substance on said ogivalportion, a charge of welding flux material exteriorly of said substance,means separating said substance and said material, means enclosing saidmaterial and defining a true ogive with respect to said body portion,and means to initiate thermal reaction of said substance upon firing ofsaid projectile.

5. A projectile comprising a body portion and an ogival portion ofreduced profile, longitudinal channels in said ogival portion, a highlyexothermic substance in said channels, covering means for said substancein said channels, an envelope on said body portion defining a true ogivewith respect to said body portion, welding flux material between saidenvelope and said covering means, and means to initiate thermal reactionof said substance upon firing of said projectile.

6. In a projectile as in claim 5, a main charge of a highly exothermicsubstance in said body portion.

7. A projectile comprising a body portion, a charge of highly exothermicsubstance in said body portion, an outer envelope spaced from said bodyportion, welding flux material between said envelope and said bodyportion, and means to initiate thermal reaction of said substance.

8. A projectile comprising a body portion, a charge of highly exothermicsubstance in said body portion, an outer envelope spaced from said bodyportion, welding flux material between said envelope and said bodyportion, means to initiate thermal reaction of said substance, and anetwork of thermally conducting material in said highly exothermicsubstance.

9. A projectile comprising a. body portion, a

20 charge of highly exothermic substance in said body portion, recessesin the outer surface of said body portion, an envelope around said bodypor- 6 tion, welding fiux material in said recesses, and means toinitiate thermal reaction of said substance.

WILLIAM NICHOLAS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,435,228 Hammond Nov. 14, 1922979,575 Schneider Dec. 27, 1910 45,024 Cleu Nov. 15, 1864 15 2,270,342Remondy Jan. 20, 1942 707,024 Semple Aug. 12, 1902 1,326,258 GraumannDec. 30, 1919 2,323,303 Bluehdorn et a1 July 6, 1943 FOREIGN PATENTSNumber Country Date 126,022 British May 8, 1919 127,265 British June 5,1919

